The invention relates generally to electronic devices, and more particularly to organic electronic devices.
In recent years, organic electronic devices, such as, but not limited to, organic light emitting devices, organic photovoltaic cells, organic electrochromic devices, organic transistors, organic integrated circuits, or organic sensors, have attracted much attention due to low cost and compatibility with flexible plastic substrates.
Currently, organic electronic devices, such as, but not limited to, organic light emitting devices, are being increasingly employed for applications, such as display applications and area lighting applications. In the last decade, tremendous progress has been made in the area of organic electronic devices. Previously, liquid crystal displays (LCDs) were employed for most display applications. However, the LCD displays involve high production and commercial expenses.
With the imaging appliance revolution underway, the need for more advanced handheld devices that combine the attributes of a computer, personal digital assistant (PDA), and cell phone is increasing. In addition, the need for new lightweight, low power, wide viewing angle devices has fueled an emerging interest in developing flat panel displays while circumventing high production and commercial expenses associated with liquid crystal displays (LCDs). Consequently, the flat panel industry is looking to employ new displays utilizing devices from other technologies, such as organic light emitting devices.
As will be appreciated by one skilled in the art, an organic light emitting device, such as an organic light emitting diode (OLED), includes a stack of thin organic layers sandwiched between two charged electrodes. The organic layers include a hole injection layer, a hole transport layer, an emissive layer, and an electron transport layer. Upon application of an appropriate voltage to the OLED lighting device, where the voltage is typically between 2 and 10 volts, the injected positive and negative charges recombine in the emissive layer to produce light. Further, the structure of the organic layers and the choice of anode and cathode are designed to maximize the recombination process in the emissive layer, thus maximizing the light output from the OLED device. This structure eliminates the need for bulky and environmentally undesirable mercury lamps and yields a thinner, more versatile and more compact display. In addition, the OLEDs advantageously consume little power. This combination of features enables OLED displays to advantageously communicate more information in a more engaging way while adding less weight and taking up less space.
Often, the organic electronic devices, such as OLEDs, include an interconnection between a first layer and a second layer that are separated by an intermediate layer that may be an electro-active or a passive material. As will be appreciated, vertical interconnects are required to electrically couple the first and second layers. Typically, the vertical interconnection is accomplished by patterning a via through the intermediate layer and then depositing a conducting material through the via such that it forms an electrical connection between the first and second layers.
However, the selective patterning of the vias and the deposition of the conducting material may generate debris that may cause defects. Further, the fabrication techniques require additional processing steps. It may therefore be desirable to develop a technique to form an electrical interconnection between two device layers and through an intermediate layer that advantageously circumvents the limitations of current techniques.